John Hagee is an Evangelical pastor at the Cornerstone Church in San Antonio, Texas, and the author of several books. His latest book claims that four blood moons will appear over America as a sign from God that a world-shaking event will soon take place. These blood moons are part of a set of consecutive lunar eclipses beginning on April 15 (tomorrow!) and continuing in six month intervals until October 2015.

This phenomenon is also known as a tetrad, when the moon is covered by the...